Ablood bank asserts that a person with type o blood and a negative rh factor (rh−) can donate blood to any person with any blood type. their data show that 49% of people have type o blood and 15% of people have rh− factor; 45% of people have type o or rh− factor. find the probability that a person has both type o blood and the rh− factor.

Probability of a person having both type O blood and the Rh− factor is %

Explanation:

The probability of a person having O blood group is

The probability of a person having Rh- factor  is

The probability of a person having either O blood group or Rh- Factor is

Hence, As per the additive rule of probability

Probability of event A and B together Probability of A Probability of A probability of either A or B

Here event A is occurrence of O blood group

event B is occurrence of Rh- factor

Substituting the given values in above equation, we get -

Probability of a person having both type O blood and the Rh− factor

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